Efficiency of Lichenicolous Fungi in Controlling Citrus Lichen Xanthoria parietina

Abstract

Lichenicolous fungi are not the same as the fungi that is the component of the lichen, which are known as lichenized fungi. This study was carried out to investigate the parasitic fungi which colonizing and attacking thalli and apothecia of citrus lichen Xanthoria parietina and the efficiency of using these fungi as lichenicolouss in its control. Several fungi were isolated from decayed thalli and apothecia and identified as Xanthoriicola physciae, Cladosporium sp., Alternaria sp., Drechslera sp., Botryodiplodia sp., Mucor sp., Aspergillus sp., Pestalotiopsis sp., Epicoccum nigrum, Fusarium sp. , and Tellogalla oliveri. Xanthoriicola physciae was the most frequent and aggressive fungus in all collected decayed samples, anatomical investigation of decayed thalli and apothecia caused by Xanthoriicola physciae showed destruction and lytic symptoms on the tissue and formation of black mass production of hypha and conidiospores in the infected thalli and apothecia. All lichenicolous fungi were isolated and cultivated on PDA and Malt yeast extract media, parasitism of lichenicolous fungi was done by spore suspension of lichenicolous fungi to fresh healthy thalli and apothecia and the results of decay and damage were recorded.